The structure of the title compound (systematic name: 6-amino-2-thioxo-2,3-dihydropyrimidin-1-ium bromide), C4H6N3S+·Br-, has two 2-thiocytosinium cations and two Br- anions in the asymmetric unit and is isostructural with 2-thiocytosinium chloride. Both six-membered rings are essentially planar. S atoms and Br- anions serve as hydrogen-bond acceptors, forming sheets parallel to (101).
Supporting information
CCDC reference: 289922
Key indicators
- Single-crystal X-ray study
- T = 295 K
- Mean (C-C) = 0.004 Å
- R factor = 0.032
- wR factor = 0.082
- Data-to-parameter ratio = 20.3
checkCIF/PLATON results
No syntax errors found
Alert level C
PLAT164_ALERT_4_C Nr. of Refined C-H H-Atoms in Heavy-At Struct... 4
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor .... 2.55
PLAT352_ALERT_3_C Short N-H Bond (0.87A) N42 - H221 ... 0.76 Ang.
0 ALERT level A = In general: serious problem
0 ALERT level B = Potentially serious problem
3 ALERT level C = Check and explain
0 ALERT level G = General alerts; check
0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
1 ALERT type 2 Indicator that the structure model may be wrong or deficient
1 ALERT type 3 Indicator that the structure quality may be low
1 ALERT type 4 Improvement, methodology, query or suggestion
Data collection: CrysAlis CCD (Oxford Diffraction, 2003); cell refinement: CrysAlis RED (Oxford Diffraction, 2003); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.
4-amino-2-thioxo-2,3-dihydropyrimidin-1-ium bromide
top
Crystal data top
C4H6N3S+·Br− | F(000) = 816 |
Mr = 208.09 | Dx = 1.847 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 1059 reflections |
a = 10.1400 (8) Å | θ = 8.0–26.0° |
b = 14.2835 (9) Å | µ = 5.69 mm−1 |
c = 10.4195 (7) Å | T = 295 K |
β = 97.480 (6)° | Prism, colourless |
V = 1496.26 (18) Å3 | 0.38 × 0.34 × 0.17 mm |
Z = 8 | |
Data collection top
Oxford Diffraction Xcalibur CCD diffractometer | 4311 independent reflections |
Radiation source: fine-focus sealed tube | 3371 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.026 |
ω scans | θmax = 30.0°, θmin = 4.1° |
Absorption correction: numerical (CrysAlis RED; Oxford Diffraction, 2003) | h = −14→14 |
Tmin = 0.131, Tmax = 0.382 | k = −20→19 |
19999 measured reflections | l = −14→14 |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.032 | Only H-atom displacement parameters refined |
wR(F2) = 0.082 | w = 1/[σ2(Fo2) + (0.0377P)2 + 0.681P] where P = (Fo2 + 2Fc2)/3 |
S = 1.11 | (Δ/σ)max = 0.001 |
4311 reflections | Δρmax = 1.02 e Å−3 |
212 parameters | Δρmin = −1.00 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0020 (3) |
Special details top
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes)
are estimated using the full covariance matrix. The cell e.s.d.'s are taken
into account individually in the estimation of e.s.d.'s in distances, angles
and torsion angles; correlations between e.s.d.'s in cell parameters are only
used when they are defined by crystal symmetry. An approximate (isotropic)
treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s.
planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor
wR and goodness of fit S are based on F2, conventional
R-factors R are based on F, with F set to zero for
negative F2. The threshold expression of F2 >
σ(F2) is used only for calculating R-factors(gt) etc.
and is not relevant to the choice of reflections for refinement.
R-factors based on F2 are statistically about twice as large
as those based on F, and R- factors based on ALL data will be
even larger. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
C21 | 0.9735 (3) | 0.91713 (19) | 0.7966 (3) | 0.0419 (6) | |
C41 | 0.8668 (2) | 0.77737 (19) | 0.8617 (2) | 0.0347 (5) | |
C51 | 0.7871 (3) | 0.8328 (2) | 0.9358 (3) | 0.0389 (6) | |
C61 | 0.8036 (3) | 0.9252 (2) | 0.9341 (3) | 0.0404 (6) | |
C22 | 0.5187 (2) | 0.36193 (19) | 0.2576 (2) | 0.0341 (5) | |
C42 | 0.6601 (3) | 0.33625 (19) | 0.0914 (2) | 0.0337 (5) | |
C52 | 0.6410 (3) | 0.2385 (2) | 0.1005 (3) | 0.0407 (6) | |
C62 | 0.5628 (3) | 0.2073 (2) | 0.1855 (3) | 0.0423 (6) | |
N11 | 0.8941 (2) | 0.96589 (17) | 0.8662 (2) | 0.0422 (6) | |
N41 | 0.8580 (3) | 0.68669 (19) | 0.8552 (3) | 0.0517 (7) | |
N31 | 0.9535 (2) | 0.82277 (16) | 0.7960 (2) | 0.0370 (5) | |
N12 | 0.5039 (2) | 0.26778 (17) | 0.2612 (2) | 0.0387 (5) | |
N42 | 0.7343 (3) | 0.3748 (2) | 0.0121 (3) | 0.0507 (7) | |
N32 | 0.5975 (2) | 0.39254 (15) | 0.1697 (2) | 0.0313 (4) | |
S21 | 1.08818 (12) | 0.96607 (6) | 0.71975 (13) | 0.0846 (4) | |
S22 | 0.45056 (9) | 0.43506 (6) | 0.35213 (9) | 0.0564 (2) | |
Br11 | 0.88089 (3) | 0.190066 (19) | 0.87814 (3) | 0.03841 (9) | |
Br12 | 0.66219 (3) | 0.610492 (19) | 0.07854 (3) | 0.03948 (9) | |
H51 | 0.725 (3) | 0.806 (2) | 0.981 (3) | 0.047 (9)* | |
H61 | 0.754 (3) | 0.970 (3) | 0.977 (3) | 0.054 (9)* | |
H52 | 0.679 (3) | 0.197 (2) | 0.056 (3) | 0.041 (8)* | |
H62 | 0.540 (3) | 0.140 (3) | 0.194 (3) | 0.046 (8)* | |
H11 | 0.897 (2) | 1.025 (2) | 0.867 (2) | 0.025 (7)* | |
H31 | 0.996 (4) | 0.790 (3) | 0.751 (4) | 0.068 (12)* | |
H12 | 0.450 (3) | 0.247 (2) | 0.308 (3) | 0.038 (8)* | |
H32 | 0.609 (3) | 0.450 (3) | 0.169 (3) | 0.046 (9)* | |
H121 | 0.814 (3) | 0.658 (3) | 0.907 (3) | 0.046 (9)* | |
H221 | 0.736 (3) | 0.428 (3) | 0.019 (3) | 0.044 (10)* | |
H222 | 0.783 (3) | 0.338 (2) | −0.029 (3) | 0.046 (9)* | |
H122 | 0.896 (4) | 0.655 (3) | 0.812 (4) | 0.057 (11)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
C21 | 0.0507 (16) | 0.0294 (14) | 0.0495 (16) | −0.0029 (11) | 0.0214 (13) | −0.0007 (12) |
C41 | 0.0386 (13) | 0.0291 (13) | 0.0385 (14) | −0.0018 (10) | 0.0132 (11) | −0.0020 (11) |
C51 | 0.0403 (14) | 0.0387 (15) | 0.0411 (15) | −0.0023 (11) | 0.0181 (12) | 0.0008 (12) |
C61 | 0.0428 (14) | 0.0382 (15) | 0.0432 (15) | 0.0037 (12) | 0.0175 (12) | −0.0041 (12) |
C22 | 0.0365 (13) | 0.0336 (13) | 0.0336 (13) | −0.0014 (10) | 0.0101 (10) | 0.0003 (11) |
C42 | 0.0384 (13) | 0.0304 (13) | 0.0341 (13) | 0.0019 (10) | 0.0115 (10) | 0.0000 (10) |
C52 | 0.0484 (15) | 0.0312 (14) | 0.0445 (15) | 0.0034 (12) | 0.0143 (12) | −0.0072 (12) |
C62 | 0.0507 (16) | 0.0270 (14) | 0.0503 (16) | −0.0034 (11) | 0.0105 (13) | −0.0042 (12) |
N11 | 0.0523 (14) | 0.0245 (12) | 0.0544 (15) | −0.0008 (10) | 0.0243 (11) | −0.0064 (10) |
N41 | 0.0661 (18) | 0.0283 (13) | 0.0680 (18) | −0.0030 (11) | 0.0366 (15) | −0.0036 (12) |
N31 | 0.0409 (12) | 0.0308 (11) | 0.0431 (13) | −0.0002 (9) | 0.0202 (10) | −0.0058 (10) |
N12 | 0.0438 (12) | 0.0342 (12) | 0.0416 (12) | −0.0058 (10) | 0.0185 (10) | 0.0024 (10) |
N42 | 0.0634 (17) | 0.0387 (16) | 0.0574 (17) | 0.0050 (13) | 0.0366 (14) | −0.0018 (13) |
N32 | 0.0392 (11) | 0.0239 (11) | 0.0329 (11) | 0.0004 (9) | 0.0131 (9) | 0.0005 (9) |
S21 | 0.1076 (8) | 0.0373 (4) | 0.1284 (9) | −0.0138 (5) | 0.0896 (7) | −0.0057 (5) |
S22 | 0.0750 (5) | 0.0424 (4) | 0.0608 (5) | 0.0033 (4) | 0.0428 (4) | −0.0057 (4) |
Br11 | 0.04337 (16) | 0.02955 (14) | 0.04514 (16) | 0.00191 (10) | 0.01647 (11) | 0.00051 (11) |
Br12 | 0.04766 (16) | 0.03080 (15) | 0.04187 (16) | 0.00000 (11) | 0.01296 (11) | 0.00186 (11) |
Geometric parameters (Å, º) top
C21—N11 | 1.346 (4) | C42—N32 | 1.360 (3) |
C21—N31 | 1.363 (4) | C42—C52 | 1.415 (4) |
C21—S21 | 1.650 (3) | C52—C62 | 1.339 (4) |
C41—N41 | 1.299 (4) | C52—H52 | 0.87 (3) |
C41—N31 | 1.349 (3) | C62—N12 | 1.360 (4) |
C41—C51 | 1.428 (4) | C62—H62 | 0.99 (4) |
C51—C61 | 1.330 (4) | N11—H11 | 0.84 (3) |
C51—H51 | 0.92 (3) | N41—H121 | 0.85 (4) |
C61—N11 | 1.360 (4) | N41—H122 | 0.78 (4) |
C61—H61 | 0.96 (4) | N31—H31 | 0.82 (4) |
C22—N12 | 1.354 (4) | N12—H12 | 0.83 (3) |
C22—N32 | 1.364 (3) | N42—H221 | 0.76 (4) |
C22—S22 | 1.647 (3) | N42—H222 | 0.88 (4) |
C42—N42 | 1.309 (3) | N32—H32 | 0.83 (4) |
| | | |
N11—C21—N31 | 114.5 (2) | C52—C62—N12 | 121.0 (3) |
N11—C21—S21 | 123.4 (2) | C52—C62—H62 | 123.2 (18) |
N31—C21—S21 | 122.0 (2) | N12—C62—H62 | 115.8 (18) |
N41—C41—N31 | 119.9 (2) | C21—N11—C61 | 123.4 (3) |
N41—C41—C51 | 122.7 (3) | C21—N11—H11 | 119.6 (18) |
N31—C41—C51 | 117.4 (2) | C61—N11—H11 | 116.9 (18) |
C61—C51—C41 | 117.5 (2) | C41—N41—H121 | 119 (2) |
C61—C51—H51 | 121 (2) | C41—N41—H122 | 125 (3) |
C41—C51—H51 | 122 (2) | H121—N41—H122 | 115 (4) |
C51—C61—N11 | 121.7 (3) | C41—N31—C21 | 125.4 (2) |
C51—C61—H61 | 125 (2) | C41—N31—H31 | 116 (3) |
N11—C61—H61 | 113 (2) | C21—N31—H31 | 118 (3) |
N12—C22—N32 | 114.4 (2) | C22—N12—C62 | 123.8 (2) |
N12—C22—S22 | 123.8 (2) | C22—N12—H12 | 117 (2) |
N32—C22—S22 | 121.7 (2) | C62—N12—H12 | 119 (2) |
N42—C42—N32 | 118.8 (3) | C42—N42—H221 | 112 (3) |
N42—C42—C52 | 123.5 (3) | C42—N42—H222 | 118 (2) |
N32—C42—C52 | 117.7 (2) | H221—N42—H222 | 130 (3) |
C62—C52—C42 | 118.1 (3) | C42—N32—C22 | 125.0 (2) |
C62—C52—H52 | 118 (2) | C42—N32—H32 | 120 (2) |
C42—C52—H52 | 124 (2) | C22—N32—H32 | 115 (2) |
| | | |
N41—C41—C51—C61 | −179.2 (3) | C51—C41—N31—C21 | 1.6 (4) |
N31—C41—C51—C61 | 0.3 (4) | N11—C21—N31—C41 | −2.6 (4) |
C41—C51—C61—N11 | −0.9 (5) | S21—C21—N31—C41 | 176.4 (2) |
N42—C42—C52—C62 | 180.0 (3) | N32—C22—N12—C62 | 0.6 (4) |
N32—C42—C52—C62 | −0.1 (4) | S22—C22—N12—C62 | −178.3 (2) |
C42—C52—C62—N12 | −0.2 (5) | C52—C62—N12—C22 | 0.0 (5) |
N31—C21—N11—C61 | 1.9 (4) | N42—C42—N32—C22 | −179.3 (3) |
S21—C21—N11—C61 | −177.0 (3) | C52—C42—N32—C22 | 0.8 (4) |
C51—C61—N11—C21 | −0.3 (5) | N12—C22—N32—C42 | −1.0 (4) |
N41—C41—N31—C21 | −178.9 (3) | S22—C22—N32—C42 | 177.9 (2) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N11—H11···Br11i | 0.85 (3) | 2.37 (3) | 3.208 (2) | 173.4 (18) |
N12—H12···Br12ii | 0.83 (3) | 2.62 (3) | 3.377 (2) | 153 (3) |
N31—H31···Br11iii | 0.82 (4) | 2.42 (4) | 3.240 (2) | 179 (6) |
N32—H32···Br12 | 0.83 (4) | 2.56 (4) | 3.345 (2) | 158 (3) |
N41—H121···Br12iv | 0.85 (3) | 2.60 (3) | 3.427 (3) | 166 (4) |
N41—H122···S21v | 0.78 (4) | 2.73 (4) | 3.309 (3) | 134 (4) |
N42—H221···Br12 | 0.76 (4) | 2.80 (4) | 3.533 (3) | 161 (3) |
N42—H222···Br11vi | 0.87 (3) | 2.58 (3) | 3.415 (3) | 162 (3) |
Symmetry codes: (i) x, y+1, z; (ii) −x+1, y−1/2, −z+1/2; (iii) −x+2, y+1/2, −z+3/2; (iv) x, y, z+1; (v) −x+2, y−1/2, −z+3/2; (vi) x, y, z−1. |